A person familiar with Zuckerberg’s thinking said the Facebook CEO plans to speak within the next 24 hours about the situation, which has unfolded in a crescendo in recent days.

Facebook disclosed late Friday that it knew Cambridge Analytica had taken users' information without their consent by obtaining it from a psychology researcher who legitimately gleaned details on users' likes and habits via a personality quiz app in 2013. The disclosure came on the eve of reports in the New York Times and The Guardian's The Observer that Cambridge Analytica got and kept personal information of 50 million Facebook users, without their permission, to build voter profiles to help in the 2016 election. The data was supposed to be destroyed.

Zuckerberg's response would be his first since details emerged of improper use of Facebook user data by Cambridge Analytica, a political consultancy with ties to President Donald Trump's 2016 campaign. Neither he nor COO Sheryl Sandberg has spoken about the issue.

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"Mark, Sheryl and their teams are working around the clock to get all the facts and take the appropriate action moving forward, because they understand the seriousness of this issue," Facebook said in a statement Tuesday. "The entire company is outraged we were deceived."

The social network is facing heat from users and lawmakers questioning why Facebook didn't inform the public about the misuse sooner and verify that the data was deleted.

It has also again drawn scrutiny over whether Facebook can protect users' personal information from third parties.

Since the revelations, lawmakers in the U.S., the U.K. and Europe have contacted Facebook seeking answers about the situation. U.S. lawmakers have urged Zuckerberg to testify before Congress. Facebook met with lawmakers Tuesday and planned to meet again Wednesday to discuss the case.

The Federal Trade Commission is probing Facebook over the matter, and the social network faces investigations from attorneys general in both New York and Massachusetts.

Cambridge Analytica, which had said all data obtained through Facebook was done "legally and fairly," revealed Tuesday it suspended CEO Alexander Nix pending a full investigation.

Facebook (FB) shares were up 0.6% Wednesday to $169.17. Shares have fallen more than 10% this week, including a 7% drop on Monday, the stock's worst drop in four years, according to FactSet.